This custom search looks at a carefully selected set of websites that offer images you can use for free on your blog, even if it is "commercial" (ie you have advertising or any other way of making money from it).
Note: some (not all) of the sites require you to include an attribution on your site.
Enter your search terms here ....
... then click on the Images tab to see the pictures
Google Custom search engines do have a feature to show images, rather than text-based web results first.
However it seems that the way they interact with Blogger at present, when I choose this option the results pop-up draws in the screen before you get a chance to enter any search terms. Until I get this sorted out, you need to click on the Images tab in the results screen to see the images-search results.